This invention relates, generally, to innovations and improvements in basement windows of the type which, in fully assembled condition, are designed to be inserted in a building foundation concrete form and remain in place after concrete has been poured around them. Basement windows of this general type are commercially available from a number of manufacturers. However, such currently available basement windows are designed to be installed in only one correct orientation. Accordingly, if one of these windows is installed upside down and/or inside out it has to be removed and usually replaced with another assembled window which is correctly installed after the opening has been repaired for its installation. The cost of the discarded basement window and labor involved in its removal and repair of the opening for installation of its replacement, add significantly to the cost of construction.